Metal planer



T. F. JUNG.

METAL PLANER.

APPLICATION FILED NOV. 8. I918- Patented Sept -.,19 1922. 7 SHEETS 9SHEET I.

K. T. F. JUNG.

Patentefl- Sept. 19,

7 SHEETS--SHEET 2.

W m 6. I I F @222 u 1 SHEETS-swan a.

PatentedSept llililiilli K. T. F. JUNG- METAL PLANER. APPLICATII'ONFILED NOV. 8.1 918.

v lli/lag K. T. F. JUNG.

METAL PLANER.

APPLICATION FILED NOV- B. 1918.

Patented Sept. 19, 1922.

TSHEETS-SHEET 4- Patented Sept 19, 1922; IsHEETs-sHEgT 5.

9, IHHII IHIIII K. T. F. JUNG.

METAL PLANER.

, 7 APPLICATION FILED NOV. 8. 191a. 1,429,?4L Patented-Sept. '19, 1922.,

" TSHEETi-SHEET s.

. JUNG.

METALPLANER.

APPLIQATION FILED NOV. a. 1918.

' MEETS-SHEET 1.

Patented Spt MQQ L Patented Sept. '19, 19229 PATENT tirrlltitii,

KARL TORSTEN FREDRIK J UN G, OF KALIVIAR, SWEDEN.

METAL PLANER.

Application filed. November 8, 1918.

To all whom it may concern:

Be it known that l, KARL TonsTEN FR D- RIK Jone, a subject of the Kingof Sweden, and resident of Kahnar, Sweden, have invented certain new anduseful Improvements in h letal Planers (for which I have filed-anapplication in Sweden, May 9, 1917), of which the following is aspecification.

In the rapid progress of machine-tools in general, as a result of theintroduction of the modern higlrspeed tool steel, the planers have beenleft far behind. In recent tables of cutting speeds the working speedfor turning is stated as 18 to 36 meters per minute, but for planing asonly 8 to 15 meters per minute. If we furthermore consider, on the onehand, the useless return-stroke, which although taking place with aspeed 2 to & times the cutting speed, represents a considerable loss ineffective cutting speed, and on the other hand the power which is spentin accelerating the reciprocating masses of table and work-piece, itisno wonder that the planer is considered in many modern workshops as arather antiquated type of machine.

The reason for keeping the cutting and return speeds so low is thereciprocating movement of the table, the change between the constantcutting speed and the constant but greater return. speed taking placeabruptly (almost instantaneously). The cutting tool consequently willhit the workpiece with a shock, which if the cutting speed should exceedthe above stated maximum cannot be sustained, neither by the tool northe work-piece, especially when the latter consists of cast material.Also the return speed has to be kept within the limits given above onaccount of the great kinetic energy which has to be taken up and to bedelivered almost instantaneously at the dead points.

Attempts have been made to increase in some degree the power of planersby giving the table two or more cutting speeds, the smaller beingcoupled in at the dead point, the greater after the tool. has enteredthe work-piece, the smaller being coupled in again before the end of theout. By these means each of the shocks at'the beginning and end of thecutting stroke will be di- Serial No. 261,698.

yided in two (or more) smaller shocks, other inconveniences remalnlng.

The present invention relates to means for so controlling the speed ofthe table, that during a double stroke ADA (see Figs. 1, 3, 6) of thetable, the speed during a certain period A B in the beginning of thecutting stroke continually increases from 0 or a small speed (V min) tothe normal cutting speed and then during a corresponding period CD atthe end of the stroke again continually decreases to O (resp. a min).During the return stroke which takes place with a greater speed,corresponding continuous speed-variations O (o min)o-O ('0 min) takeplace. The length of stroke, A D, 1s, as generally known, effected bymeans of a suitable reversing mechanism, actuated by tappets or dogs onthe table.

By the mentioned continuous speed-variations the tool enters the work inthe vicinity of point A with a very small speed andconseque'ntly'without any shock or blow. The velocity then continuouslyincreases to point B, where the constant cutting speed starts.Immediately before point D the tool leaves the work without shock. Bythese means the 1 cutting speed is limited only by the strength of thetool and may be as high as in modern high speed lathes. When a number ofwork pieces are mounted on the table similar.

speed-variations may, according to certain constructional forms of theinvention, be effected at points corresponding to the said differentwork-pieces.

As the return stroke has similar acceleration and retardation periods DE, F A at the beginning, and end, instead of the indetermined and almostinstantaneous reversal by means of belt-shifting mechanism or similar,and as furthermore the speed curve during these periods may be chosen soas to keep the accelerating forces constant or variable with acomparatively low maximum value, the return speed may also be increasedto a multiple of the usual, while keeping the said maximum value of theaccelerating forces below the values in corresponding usual planers.

F or a fuller understanding of the invention reference is had to theaccompanying drawings in which Figs. 1, 6 and 20 are speed diagrams of acomplete cycle of reciprocating movement in planer construction,embodying different forms of the invention;

Fig. 2 is sectional plan view taken through the bed driving shafts;

Fig. 3 is a diagrammatic View of a detail,

I Fig. 4 is a side elevation; and

Fig. 5 is a cross section on the line AB- CD in Fig. 4,

Fig. 7 is a sectional plan view, taken on a line through the bed drivingshafts;

Fig. 8 is a vertical longitudinal section through the machine; I

Fig. 9 is a vertical section through the middle of the machine;

Fig. 10 is a horizontal section on the line ABC-D in Fig. 11;

Fig. 11 is a side elevation the lower part thereof being a section onthe line E-F in Fig. 7; and

Figs. 1219 are diagrammatic illustrations of the table actuatingmechanism in four different positions.

Figs. 2124 show inhorizontal section, cross section of a detail, sideview, and longitudinal section respectively, a construction, pertainingto Fig. 20. Fig. 23 shows the dogs 20" and 21 in Fig. 23 in plan view.

In the constructional form shown in Figs. 25, 1 is the driving pulley,the movement of which is transmitted by the pinion 3, and spur gear 4 tothe shaft 15, connected with the shaft 16 through either one of thepairs of gears 5, 6 or 7, 8. All these gears are loosely mounted ontheir shafts. By means of the coupling K either gears 5 and 6 or 7 and 8of these gears are coupled to the shafts 15, and 16, respectively. Thegears 5 and 6 are two elliptical gears and therefore change the constantangular velocity of the shaft 15 to avariable angular velocity of theshaft 16. The gears 7 8 are two ordinary spur gears and transmit to theshaft 16 rotary motion, the angular velocity of which equals the maximumvalue of the angular velocity transferred to the shaft 16 by theelliptical gears 5 and ,6 (positionII, Fig. 3). The movement of theshaft 16 is transmitted by means of the pinion 9 and spur gears 10, 11to two shafts 17, 18, on which are keyed two spur gears 12, 13 gearingwith the usual rack 14 on the under side of the table. The gears 9, 12,13 are fixed on their respective shafts, but the gears 10 and 11 areloosely mounted on their shafts. The coupling K in the position Iconnects the gear 10 to the shaft 17 and the driving gear 12, whichtherefore moves the table in the direction shown by the arrow 0,corresponding to the cutting stroke. In the position II the coupling Kconnects the gear 11 to the shaft 18 and the gear 13, which moves thetable in direction of the arrow at, corresponding to the return stroke.The return speed is considerably in excess of the cutting speed, as isseen by the proportion between the diameters of the gears 10 and 11.

To bring into action the mechanism for acceleration, retardation andreversal of the table, two movable dogs 19, 20 are slidably fixed to thetable. The shorter tongues of said dogs are acting on the mechanismwhich brings the coupling K and the elliptical gear in action, and thelonger tongues act on the mechanism, which. brings into action thecoupling K to effect the reversal of the table. Each of the shortertongues acts on the working face of one of the two-armed levers 21, 22,the lower arms of which form cog-sectors co-acting with the spur-wheels24, 23 of which the latter meshes with a spurwheel 25, attached to thesame shaft asthe wheel 24, thus coupling the two levers 21, 22 togetherand causing them to swing in opposite directions. The rack 26 gearswiththe wheels 24, 27, the latter of which is attached to a shaft 28, theend of which is threaded and has a'nut 29 acting on the lever 30, whichmoves the double coupling; K in the one direction or the other. Theelliptical wheel 6 is connected to a wheel 32 gearing with a wheel 33 ofequal diameter on the shaft 34, underneath the shaft 16. On the otherend the shaft 34 carries a circular disc 35 having a slot 48, in whichthe roller 36 on the free end of the single-armed lever 37 can fall in,in a certain position (II, Fig. 3) of the elliptical wheel 6 or of thedisc 35, which make one revolution simultaneously. The lever 37 has,opposite to the roller 36, a small pin 38, which looks the rack 26, whenentering a slot therein. When the roller 36 falls into the slot at thepin 38 passes out of the slot in the rack 26, thereby releasing" thelatter, which will move under the action of the spring 39 to its rightend position, corresponding to position II of the coupling K, 1

thus uncoupling the elliptical gear 5, 6 and coupling in' the ordinaryspur gear 7, 8

To reverse the motion of the table by means of the double coupling K thecoupling lever 47 has a third arm 46 which is moved in the one directionor the other by means of the reversing anchor 40, the link 41, the lever43, the shaft 44, the arm 45 and the link 42.

Fig. 1 represents the speed-diagram of this mechanism. A D representsthe stroke of the machine. The cutting speed 0) is plotted upwardsandthe return speed c downwards. The speed-curve during a double strokeof the table is therefore represented by the lines A B C D E F A. Whenthe table reaches the position A and is going to start the cutting workstroke, the longer tongue of the dog 20 has hit the left working face ofthe reversing anchor 40, which at this line is in its uppermont positionand has forced said face down in the position 1 shown in Fig. 3, thusbringing the coupling K from position II to position I in which itremains during the whole cutting stroke. The coupling K is at the startof the cutting stroke in the position I, the movement, therefore, beingtransmitted by the elliptical wheels 5, 6, which during the last part FAof the return stroke have made half revolution and are at this moment inposition I, Fig. 3. While the gear 5 makes half a revolution from theposition I to the position II, the slide moves from A to B with acontinuously increased speed. At the point B it has reached its fullcutting speed 1;. During the way F-A-B the elliptical gear 5, 6 andconsequently also the disc 35 has made eX- actly one revolution, and theslot now reaches the roller 36 and is engaged thereby thus releasing therack 26, which is forced by the spring 39 to its right end-position,thereby uncoupling the elliptical gear 5, 6 and coupling in the ordinarygear 7, 8. The table then moves from B to C at the constant cuttingspeed 12. At the point C the shorter tongue of the dog 19 hits theworking face of the lever 21 and forces it from position a to positionZ), thus moving the rack 26 from its right to its left end-position, andcoupling the gear 7, 8 and coupling in the elliptical gear 5, 6, whichstarts in revolving half a revolution from position II, F ig; 2 toposition III, causing the speed of the table to decrease continuallyfrom '2) to o min during the way C-D. When the disk 35 starts to rotatethe roller 36 leaves the slot 48 and rolls on the periphery of the saiddisc, causing the pin 36 to fall in its slot in the rack 26, thuslocking the latter in the left end-position. At the point D the longertongue of the dog 19 hits the right working face of the reversing anchor40 and the coupling K is reversed from position I to position II. Thegear 13 is then brought in action, the return stroke is started and thesame course, as in the cuttin stroke is repeated, i. e. the reversals ofthe coupling K take place at the points E and F. The proportion betweenthe speeds and 'v, is determined by the diameters of the wheels 10 d 11It' (1 t th t an 1s ev1 en a as thedistances AB and AF are performed inthe same time (corresponding to half a revolution of the wheel 5). Thatthe distance AF and ED in the return stroke are greater than thecorresponding distances AB and CD in the cutting stroke or, conversely,that FE is smaller than BC, results in a material advantage, inasmuch asthe accelerating forces during the return stroke will be c011 siderablysmaller, than they would be if said distances were equal and as it issaid accelerating forces which limit the return speed o When forinstance in the particular arrangement 30, the accelerating forcesduring the return stroke are only three times the same forces during thecutting stroke, while they should have been 9 times as great if AF hadbeen equal to AB. To this advantage, however, is incident thedisadvantage, that the smallest possible stroke of the machine AF +EDwill be greater than otherwise. When however a smaller stroke is desiredit is possible to let the planer work as a usual planer, by letting thecoupling Ii stay in position II. In this case it is however necessary tocouple in the smallest speed.

The cutting steel enters and leaves the work piece at points G and II,respectively, which can be located close to the end points of thestroke, said end points with the transmission of motion according to thepresent invention being absolutely fixed and not as in the usual planersdetermined by the masses of table and work piece and by the elasticityof belts or resilient couplings which take up the kinetic energy. Thespeed with which the steel enters and leaves the work piece,respectively, may consequently be brought close to 41 min, whereby evenvhen' cutting speeds as high as 30 to 36 meters per minute are used theshocks will be negligible.

In the constructional forms described below n min may be reduced to O,and the shocks furthermore lessened.

/Vhen high speeds are used, the accelerating forces nevertheless will begreat. As, however, according to the present invention the pulley l iscontinuously driving and its shaft therefore always rotates in the samedirection, it is possible to place a fly wheel 2 on the same, taking upenergy during the periods CD and Al and delivering the same during theperiods AB and ED. No energy will then be lost by the reciprocatingmovement.

Figs. 7l9 show another constructional form for the transmission ofmotion pertaining to Fig. 6. It differs from the form shown in Figs. 25mainly in that the speed of the table decreases to 0, and that theacceleration and retardation periods AB, CD during the cutting strokeare equal or nearly equal to the corresponding periods ED, FA during thereturn stroke. Consequently the speed,'with which the steel. enters andleaves the work piece, is brought down very nearly to O. Theaccelerating forces during the return stroke become greater, but may betaken up by a fly-wheel.

1 (Fig. 7) is the drivingpulley mounted on the shaft 17 which alsocarries the fly wheel 2 and the three spur gears 3, 5 and 8 which areloosely mounted thereon and may be coupled by means of the couplings K Kand K. The gear 3 engages directly the gear 4 attached to the shaft 18,and the gear 5 engages by means of an intermediate gear 6 the gear 7attached to the same shaft 18'. The gear 8 finally engages a gear 9 onthe shaft 20. The gear 9 carries a pin 16 having movement in a slit 22on the spur sector 10, oscillating on the shaft 21, said sectorreceiving a reciprocating movement when the gear 9 rotates in thedirection of the arrow at, which movement is transferred to the spurgear 11 engaging the sector 10. The spur gear 11 during one revolutionof the gear 9 receives an angular velocity varying between when the pin16 is in the positions I, III (Fig. 8) and two different maxima in thepositions ll, TV respectively of said pin. The former and smaller isproportional to the cutting speed 12 and the latter and greater to thereturn speed '0 By one of the wheels 4t, 7 or 9 whichever may be at themoment in the transmission train the movement is transmitted by means ofthe spur gear 12, to the gear 14., driving the rack 15 of the table.

The transmission of motion is indicated in the table following below,inwhich for every one of the couplings K K K I is the position, in whichthe corresponding gear 3,

v or 8 is engaged and H the position, in

which the same gears disengaged. The wheels marked with arrows in Figs.4 and 5, always move in the dlrection shown by these arrows, the othergears during difl'erent periods move in opposite direct ons.

The mechanism for accelerating and retarding the movement of the tableis also in this case brought into action in the points CF of the diagramby means of two movable dogs 23, 24-, Figs. 11, 12, i l, 1.6, 18, on thetable. The reversal of the table by means of the mechanism 16, 12, willas is easily realized by the character of said mechanism, in this casefollow automatically. The dogs 23, 24; are acting on the working faces25 and 26 of the coupling anchor 27 which acts on the curve slide 28,Figs. 10, 11, in the one direction or the other by means of the link 29,the lever 30, the inner shaft 3 the lever 32, Figs. 7, 9, 10, in theopposite end of said shaft, the link 33, the single-armed lever 34 andthe link 35.

.Said curve slide 28 by means of its V- shaped curve 36 moves the roller37, ailixed on the lower side of a sliding bar 38 having square section.FiXed on the top of said bar 38 are the pins 6 0 d 6 7. The pins 32 0 0are rigidly attached to the. sliding bar and the pins d and f areslidably arranged in their respective holes in the bar 38 and arepressed downwards against arms 39, 40, Fig. 10,by small springs,notshown. The arm 40 is fixed to the inner shaft'il and the arm 39 is fixedto the hollow shaft 4.2. At its opposite end the shaft 41' can. ries an21.1'111'423, and the shaft 42 carriesa. similar arm 44:. Each of thesearms carries av roller 45 respectively 46, Figll,

which is pressed as by means of.a spiralspring 49 against a curve 47 or48, respectively the elevated parts of which cover ing each 180 of thecircumference. The curves 47., 48 Fig. 10, are rigidly connected to thespur wheel 9, also carrying two tapered dogs 50, 51 adapted to act onthe roller 52 of the lever 84L at the points E. 13., Fig. 6, where theaccelerating. mechanism 8, 9, 16, 22, 10 has to be uncoupled. Thecouplings K K and K are brought in their active or inactive position bymeans of coupling levers 53, 5e, 55, Figs. 11, 12, let, 16, 18, turningon pins 56, 57, 58'. At their. right ends said coupling levers carryprojections adapted to cooperate with the pins 5 0 03 e f Figs. 10, 13,l5, 17, 19, of the sliding bar 38, in such a way that the pin 5 isembraced by the projection of the lever 58 of the coupling-K, and thecorrespondingprojections of the lever arms 54, 55 of the couplings K Kare situated normally, the former between the-pins c and d and thelatter between the pins e and f Y While the table is performing itsworking stroke from B to C, see the diagram, Fig. 6, the various partsof the table actuating mechanism are in the position, shown in 7 movedto its left end-position, Fig. 15. By the roller 37 the sliding bar 38.is then brought down in the position Fig.15. The fix pins 6 0 force thecoupling levers 53, 54 from the top positions, shown inFig. l3, andmoves same to the lower positions in Fig. 15, thus bringing the couplingK, Fig. 7 ,in action and uncoupling the coupling K As the roller 45 ofthe arm 43 is presently in engagement with not-elevated part of thecurve 47, the slidable pin f is in its lower inactive position and thecoupling lever 55 passes over 7' when the sliding bar 38 takes theposition in Fig. 15. lVhen the coupling K isthus brought into action atpoint C,the pin 16 is in position II. and starts its rotation in thedirection of the arrow a, Fig. 8.- By means of the wheels 8, 9, the pin16' working in the slit 22 of the spursector 10, and the wheels 11, 12,14:, the motion is transmitted to the table to move the latter.

from C to D at a speed which continuously decreases to 0, when the pin16,- rotates from position II to position III. When the pin moving fromposition III to position IV, the table starts its return stroke and goesfrom D. to E at, a speed, which increases from 0 to the normal returnspeed 11 At point E the wheel 9 and consequently also the tapered dogs50 and 51 have made half a revolution and take the positions, shown inFig. 16. The dog 51 at this moment has hit; the roller 52 and forces thelever 34 from the positions Z, Fig. 14, to the position j, Fig. 16, thusbringing the curve slide 28 back to its middle position, As the roller46' of the arm 44 is now in the inner position and the pin d is in itslower, inactive position, the slide bar 38, when brought by the curveslide 28 to its top position, Fig.

, 17 raises the coupling levers 53, 55 to their top positions, whileleaving the lever 54 in its lower, inactive position, thus coupling Kand coupling in K By means of the spurwheels 3, 4, 12, 14 the table isthen caused 30 continue its return stroke from E to F at a constantspeed o At point F the dog 24 hits the working face 25 and it willeasily be seen that the different parts will take the positions shown inFigs. 18, 19 and the pe riods of retardation FA and acceleration AB willfollow when the pin 16 makes half a revolution from IV to II.

That the periods AB and CD in this case are not in the same proportionto the periods AF and ED as '0 to o as formerly but are nearly equal toone another depends obviously thereupon that the corresponding ways cfthe pin 16 are unequal. It is also evident that it is possible todetermine the proportion within certain limits by choosing the length ofthe slit 22 and its distanoe from the shaft 21 accordingly.

Figs. 21-24 show a third constructional form of the mechanism fortransmission of motion pertaining to Fig. 20 which has the advantage,that it makes it possible to give any desired form to the speed diagram,that is, the absolute value of the speeds o and c as well as the form ofthe speed curve may be arbitrarily determined by placing dogs ofcorresponding form and position on the table. Fig. 20 shows a suitableform of the speed curve, a modification of the same being shown by thedot and dash lines.

1 is the driving pulley,the shaft 25 of which also carries the fly wheel2 and the pinion 3 which meshes with a gear 4", attached to the shaft26". The gear 4" is connected to another smaller gear 6", whichconstitutes the inner gear in a planetary gear arrangement 5", 6', 7",8", the outer gear 5 of which, by means of an outer cog rim, drives thegears 29" and 30 on the shafts 27-, 28 carrying also the gears 23",

24, gearing with the rack 31 of the table. The gear 23 drives the tableduring the cutting stroke AD, the gear 24 during the return stroke DA,according as the coupling K is in the position I or II. The planetarygears 7,8 rotate on pins 9", 10", attached to a disc 11" which looselyrotates about the shaft 26 and is fixed to the worm gear 12'. This wormgear 12" gears with the worm 13 on the shaft 85 as which by means of aspur gear drives a friction disc 14", the working surface of which isparallel to the shaft 25. Another friction disk 16 is slidably mountedon this shaft and can, by means of a suitable coupling lever 17 (Fig.23), be moved in radial direction over the disc 14". 15 is anotherfriction disc, which is held against the disc 16 by means of a spring.

WVhen the disc 16 is moved to inoperative position relatively to thedisc 14", and the latter therefore comesto rest, the gears 12", 11 andthe pins 9, 10 also will come to rest. Through the gears 3", 4 and 6 andthe planetary wheels 7, 8" rotary motion of shaft 25" will betransmitted in the direction given by the arrows to the gear 5", whichwill then rotate in the direction of the arrow a (Fig. 24) with acertain speed. In reality, however, the disk 16" under the influence ofsuitable dogs on the table will successively assume positions marked Ito III and intermediate positions on the friction disc 14". When thedisc 16 is in one of these positions it will cause the disc 14" torotate in the direction corresponding to the direction of rotation ofthe disc 16 indicated by the arrow (Fig. 24). Through the worm 18 thisrotation is transmitted to the worm gear 12 and to the disc 11" and thepins 9, 10", which are then caused to rotate in the direction of thearrow 6 (Fig. 24) imparting a corresponding rotation to the gears 7, 8".The nearer the disc 16 is brought to the centre of the disc 14", themore rapidly the disc 14 and therefore also the pins 9, 10 will rotate.The angular velocity of outer wheel 5 then decreases in such a mannerthat for instance the position I of the disc 16" corresponds to thereturn speed c of the table, the position II to the working speed c andthe position III to the speed 0 of the same. It is therefore ob-- viousthat by giving the working surfaces of the dogs a suitable height, thevalue of the speeds o and 11 may be varied, and that by choosing asuitable length and form of these working surfaces, it is possible todetermine arbitrarily the length of the acceleration and retardationperiods as also the form of the speed curve during these periods, as isshown by the full line curve and the dash and dot curve part-s AB and ABrespectively, in Fig. 20. By placing cated by the dot and dash curvepart 01 (Fig. 20). In this way it is possible to cut with great speedeven such work pieces which have two or more different surfaces in thesame plane, without danger of breakage of working tool or material whenthe tool enters or leaves the work piece.

The work of the machine during a double stroke of the table isillustrated by the fol-.

lowing table.

Position resp. Position Part of the moveof the stroke AD. ment couplingof the K. wheel lfi.

A-B III-II I II v I II-IIi I IIII II I II IIII II The mechanism. foracceleration, retardation and reversal of the table is actuated by twomovable dogs 20.21 on the table. Said dogs on their lower surface formguide-ways for governing the roller 32 moving by means of the lever 33,the shaft 34', the lever 36", the link 37 and the lever 17 the frictiondisc 16 between its different positions I to III. The ways for theroller 32 are formed on the one side by the vertical walls of theV-shaped grooves in the dogs 20", 21 on the other side of the tongues38", 39", which turn on pins 40 41 and are kept by springs, not shown,in the positions shown in Fig. 23.

The mechanism for reversing the table, consists of the usual reversinganchor 42", which, as is easily realized, is actuated at the end pointsA and D by the tongues 43", 44 on the dogs 20", 21". The reversinganchor is fixed to the inner shaft 45", which by means of the lever 46',the link 47" and the three armed lever 4E8 actuates the coupling K.

lihen the table performs its stroke from B to C, Fig. 20, the coupling Kis in position I, and the disc 16 in position II, as indicated in Fig.21. The roller 32" has a corresponding position on the line B C, 23.When the table reaches the point C, the point C of the dog'20reaches theroller 82'. Then the table moves from C to D the roller 32 slides fromC' to D, pressing down the tongue 38 by means of the mechanism 83, 34,36",37, 17" to move the disc 16 from position II .to

position III. At point D the tongue 43" hits the right working face ofthe reversing anchor 42 and brings the coupling K from position I toposition II, thus reversing the table. ,When the table then is movingfrom D'to E the roller 32 passesfronr'D" to E and moves the disc 16 fromposition III to position I, accelerating the table from the speed 0 tothe normal return speed 41 At the other'end of the strokethe same actionis repeated under the control ofthe dog 21. a

It is obvious that in this constructional form, it is possible to omitthe gears 24a, 30 and effect the reversal by causing the frictionwheel'16 to act on different sides of the centre of friction disc 14during the cutting and return strokes. This; would, h'owever,-requi'rea' considerably increased power, as the pressure betwee n the thread'BOof the worm 13 and the cogs'of worm gear 12 in this case wouldcounteractthe move? ment."

j It is obvious'that the invention is not lim; ited to theconstructionalforms shown; v 85 I claim:

1. In -a planer, the combination" with'a table and the planing tool, oneof which is movable,-of a constantly rotating driving shaft, anothershaft, means'for changing the constant rotation of said driving shaft'toa variable rotation of said other shaft, and means to impart fromsaid other shaft and to the movable memberof the planer a substantiallyuniform motion during th'e greater part of the cutting stroke and aretarding motion during a' relatively small part of the cutting strokeat the end thereof.

2. In a planer,'the combination with "a table and the planing tool, one;of which is 10 movable, of a constantly rotating driving shaft,another'shaft, means for changing'the constant rotation of said-drivingshaft to a variable rotation of said other shaft, and means to impartfrom saidother shaft-and to the movable member of the planer aniaccelerating motion at the beginning'of the cutting stroke during arelatively small part thereof and a substantially uniform motion duringthe greater part of the stroke.

3. In a planer, the combination with. a table and the planing tool, oneof which is movable, of aconstan'tly rotating driving shaft, anothershaft, means to change the constant rotation of said driving shaft to avariable rotation of the said other shaft, and means to impartffrom thesaid other shaft and to the movable member of the planer an acceleratingmotion at thebeginning of the cutting stroke during arelatively smallpart thereof, a substantially uniform motion during the greater partofthe cutting stroke, and a retarding motion during a relatively smallpart of the cutting'stroke at. the end thereofJ i w 4:. In a planer,thecombinationwith a table and the planing tool, one ofiwhich-ismovable, of a constantly rotating driving shaft, another shaft, means tochange. the constant rotation of saiddrivingfshaft toa 130 variablerotation of the said other shaft, and means to impart from the saidother shaft and to the movable member of the planer during the cuttingstroke and the return stroke an accelerating motion, a substantiallyuniform motion and a retarding motion, the rate of motion during thereturn stroke being greater than during the cutting stroke.

5. In a planer, the combination with a table and the planing tool, oneof which is movable, of means operative to impart to the movable memberduring the cutting stroke and the return stroke an accelerating motion,a' substantially uniform motion and a retarding motion, said means beingso con structed and arranged that the periods of acceleration andretardation during the return stroke are greater than during the cuttingstroke, that the period of uniform motion is smaller than during thecutting stroke and the rate of motion during the return stroke greaterthan during the cutting stroke.

6. In a planer, the combination with the table and the planingtoolhaving relative reciprocating movement, of a constantly rotating drivingshaft, means for transmitting from said shaft and to the movable memberof the planer a movement gradually accelerated from a low value to amaximum value through a fixed distance at the beginning of each strokeand gradually retarded from said maximum value to a low value through afixed distance at the end of the stroke, said means being constructedand arranged to accelerate the speed during the return stroke to agreater maximum value than durin the cutting stroke.

In a planer, the combination with the table and the planing tool havingrelative reciprocating movement, of a constantly rotating driving shaft,means for transmitting from said driving shaft and to the movable memberof the planera movement continuously accelerated from a low value to amaximum value through a fixed distance at the beginning of each strokeand continuously retarded from said maximum value to a low value througha fixed distance at the end of the stroke, said means being operative toaccelerate the speed during the return stroke to a greater maximum valuethan during the cutting stroke, and means for maintaining substantiallyconstant speeds between the periods of acceleration and retardation.

8. In a planer, the combination with the table and the planing toolhaving relative reciprocating movement, of means operative to make thereturn speed greater than the cutting speed, and means for graduallyincreasing the speed through a fixed distance at the beginning anddecreasing the speed through a fixed distance at the end of each stroke,said means being operative in such manner that the distances throughwhich the acceleration and retardation take place are greater during thereturn stroke than during the cutting stroke.

9. In a planer, the combination with the table and the planing toolhaving relative reciprocating movement, of means operative tocontinuously increase the speed through a fixed distance at thebeginning and continuously decrease the speed through a fixed distanceat the end of each stroke, means for temporarily decreasing and thenagain increasing the speed during the cutting stroke, and means formaintaining a substantially constant speed between the periods ofacceleration and retardation, said means being operative to give agreater speed during the return stroke than during the cutting stroke,

10. In a planer, the combination with the table and the planing toolhaving relative reciprocating movement, of a constantly rotating drivingshaft, means for transmitting from said shaft and to the movable memberof the planer a movement gradually retarded from a maximum value to zerothrough a fixed distance at the end of each stroke and again graduallyaccelerated from zero to another maximum value through a fixed distanceat the beginning of the following stroke, and means for maintaining asubstantially constant speed between the period of acceleration andretardation, said means being operative to give greater speed during thereturn stroke than during the cutting, stroke.

11. In a planer, the combination with the table and the planing toolhaving relative reciprocating movement, of means for graduallyincreasing the speed from a low value to a maximum value through a fixeddistance at the beginning of each stroke and for gradually decreasingthe speed from said maximum to a low value through a fixed distance atthe end of the stroke, said means being operative to accelerate thespeed to a greater maximum value and through a greater distance duringthe return stroke than during the cutting stroke.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

KARL TORSTEN FREDRKK JUNG. Witnesses:

J OHAN MARKMAN, GRETA PRIEN.

